Aqueous water and oil repellent composition

ABSTRACT

An aqueous water and oil repellent composition is produced by emulsifying a an acrylate or methacrylate copolymer containing perfluoroalkyl or perfluoroalkenyl group in the presence of a quaternary ammonium compound in an aqueous medium containing an organic cosolvent which gives a stable dispersion and imparts excellent water and oil repellent properties to the textile and carpets.

FIELD OF INVENTION

The present invention relates to a composition for treatment of textileand carpets for imparting excellent water repellency, oil repellency andsoil releasability. The present invention relates to the use of a waterand oil-repellent composition which is safe for exposure to humans andanimals and presents little environmental impact while providing adurable water and oil repellency to a material to be treated with in ahighly simplified method of application.

BACKGROUND OF THE INVENTION

Hitherto, various treatment methods have been proposed in order toimpart water, oil and soil repellency to a textile or to a carpet. Forexample, a process often referred to as “exhaust process” of treating atextile comprises of lowering the pH of a treatment liquid, applying thetreatment liquid to the textile, thermally treating the textile withsteam, washing the textile with water, and dehydrating the textile asdescribed in the U.S. Pat. Nos. 5,073,442, 5,520,962, 5,516,337 and5,851,595 and the International Publication WO 98/50619.

The U.S. Pat. No. 5,073,442 discloses a method of treating a textile,comprising of conducting an “exhaust process” by using a water- andoil-repellent agent comprising a fluorine-containing compound, aformaldehyde condensation product and an acrylic polymer. The U.S. Pat.Nos. 5,520,962 and 5,851,595 disclose a method of treating a carpet,comprising of conducting an “exhaust process” by using afluorinc-containing compound and a polymeric binder. The U.S. Pat. No.5,516,337 discloses a method of treating a textile, comprising ofconducting an “exhaust process” by using a fluorine-containing water-and oil-repellent agent and a metal compound such as aluminum sulfate.The International Publication WO 98/50619 discloses a method of treatinga carpet, comprising of conducting an “exhaust process” by using afluorine-containing water- and oil-repellent agent and a salt such as amagnesium salt. These methods mainly use the water and oil repellentagents in combination with the stain-blocking agents and can give waterrepellency and oil repellency when using the “exhaust process.” The U.S.Pat. No. 7,147,669 describes an invention wherein no use of a stainblocking agent is made using an “exhaust process.”

It is obvious from the applications described above that the process ofinducing water and oil repellency to fabrics is expensive and tedious.There is therefore a need to develop a simpler, less expensive process.The present invention provides such a method of preparing a treatedtextile, comprising of steps of simply preparing a treatment liquidcomprising a water- and oil-repellent agent and applying the treatmentliquid to a textile by soaking the textile in it, wherein the water- andoil-repellent agent comprises at least one fluorine-containing compoundselected from the group consisting of a fluorine-containing polymers anda fluorine-containing low molecular weight compound, the water- andoil-repellent agent or the treatment liquid additionally contains acationic emulsifier and/or its salt.

The present invention also provides a textile prepared by theabove-mentioned method, and a water- and oil-repellent agent used in theabove-mentioned method. A polymer of polymerizable compound having aperfluoroalkyl or perfluoroalkenyl group and an acrylate or methacrylategroup can be used as a water and oil-repellent for a fibrous fabric. Inorder to obtain the perfluoroalkyl group containing (meth)acrylatecopolymer, a polymerization method such as bulk polymerization, solutionpolymerization dispersion polymerization or an emulsion polymerizationis used. Emulsion polymerization is industrially advantageous becausethe copolymer can be obtained directly in the form of an aqueousemulsion in the presence of a surfactant and co-solvent.

However, the water and oil-repellency of a fibrous fabric treated withusual conventional aqueous dispersions is not satisfactory for variousreasons. From economical view points, there is a need to develop a waterand oil repellent composition that will be capable of imparting waterand oil-repellency when used in small quantities, a water andoil-repellent composition capable of achieving the repellency effectswhen cured at a low temperature, and a water and oil repellentcomposition capable of providing a high production yield which is lessinfluenced by processing conditions.

SUMMARY OF THE INVENTION

One of the objective of the present invention is to provide an aqueouswater and oil-repellent composition which can impart durable water andoil-repellency to fibrous materials and exhibits excellent storagestability.

The present invention provides aqueous water and oil-repellentcomposition comprising:

-   -   (A) A perfluoroalkyl or perfluoroalkenyl group compound        containing acrylate or (meth)acrylate copolymer groups    -   (B) A surfactant comprising quaternary ammonium compound    -   (C) An aqueous medium

DETAILED DESCRIPTION OF THE INVENTION

In the first step of the method of the present invention, the treatmentliquid comprising the water- and oil-repellent agent is prepared. In thestep two of the method of the present invention, the treatment liquid isapplied to the textile by known procedures such as by immersion,spraying and coating. Usually, the treatment liquid is diluted withwater and is adhered to surfaces of the substrate by the methodsdescribed above such as an immersion coating, a spray coating and a foamcoating to a fabric (for example, a carpet cloth), a yarn (for example,a carpet yarn) or any other fiber in raw or processed form. Ifnecessary, the treatment liquid is applied together with a suitablecross-linking agent, followed by curing. It is also possible to addmothproofing agents, softeners, antimicrobial agents, flame retardants,antistatic agents, paint fixing agents, crease-proofing agents, etc. tothe treatment liquid. The concentration of the active component (thatis, the fluorine-containing compound) in the treatment liquid contactedwith the substrate may be from 0.05 to 10 parts by weight, based on thetreatment liquid.

In the step three of the method of the present invention, the textile iswashed with water and dehydrated. In order to remove excess water, thetextile is dehydrated by a usual dehydration procedure such as acentrifuging and vacuuming procedure. After the step three, the textilecan be further dried.

In the emulsion polymerization, there can be used a method ofemulsifying a monomer in water in the presence of a polymerizationinitiator and an emulsifying agent, replacing by nitrogen, andcopolymerizing with stirring at the temperature within the range, forexample, from 50 to 80 C for 1 to 10 hours. As the polymerizationinitiator, for example, water-soluble initiators (e.g., benzoylperoxide, lauroyl peroxide, t-butyl perbenzoate, 1-hydroxycyclohexylhydroperoxide, 3-carboxypropionyl peroxide, acetyl peroxide,azobisisobutylamidine dihydrochloride, azobisisobutyronitrile, sodiumperoxide, potassium persulfate and ammonium persulfate) and oil-solubleinitiators (e.g., azobisisobutyronitrile, benzoyl peroxide,di-tert-butyl peroxide, lauryl peroxide, cumene hydroperoxide, t-butylperoxypivalate and diisopropyl peroxydicarbonate) can be used. Thepolymerization initiator is used in the amount within the range from0.01 to 2 parts by weight based on 100 parts by weight of the monomer.

In order to obtain copolymer dispersion in water, which is highlydesirable to enhance stability of application during storage, it isdesirable that the monomers are atomized in water by using anemulsifying device capable of applying a strong shattering energy (e.g.,a high-pressure homogenizer and an ultrasonic homogenizer) and thenpolymerized with using the water-soluble polymerization initiator.Examples of the water-soluble organic solvent include acetone, methylethyl ketone, ethyl acetate, propylene glycol, dipropylene glycolmonomethyl ether, dipropylene glycol, tripropylene glycol and ethanol.The water-soluble organic solvent may be used in the amount within therange from 1 to 50 parts by weight, e.g., from 10 to 40 parts by weight,based on 100 parts by weight of water.

The substrate to be treated in the present invention is preferably atextile, including a carpet. The textile may be animal or vegetableorigin natural fibers such as cotton, hemp, wool and silk; syntheticfibers such as polyamide, polyester, polyvinyl alcohol,polyacrylonitrile, polyvinyl chloride and polypropylene; semisyntheticfibers such as rayon and acetate; inorganic fibers such as glass fiber,carbon fiber and asbestos fiber; and a mixture of these fibers. Thepresent invention can be suitably used in carpets made of nylon fibers,polypropylene fibers and/or polyester fibers, because the presentinvention provides excellent resistance to a detergent solution andbrushing (mechanical).

The textile may be in any form such as a fiber and a fabric. When thecarpet is treated according to the method of the present invention, thecarpet may be manufactured using treated fibers or yarns or themanufactured carpet may be directly treated according to the presentinvention. The water- and oil-repellent agent diluted with water to thecontent of 0.02 to 30% by weight, preferably 0.02 to 10% by weight.

DETAILED DESCRIPTION OF THE INVENTION

The critical components of the present invention include:

-   -   a) perfluoroalkylacrylate    -   b) other copolymerizable compound    -   c) a quaternary ammonium compound    -   d) reaction initiator, e.g., AIBN    -   e) chain transfer agent, e.g., alkyl mercaptan    -   f) water miscible organic solvent    -   g) water

Non-limiting specific examples of the polymerizable compound having theperfluoroalkyl or perfluoroalkenyl group and the acrylate ormethacrylate groups are represented below:

-   -   CF₃(CF₂)₇(CH₂)₁₀OCOCH═CH₂    -   CF₃(CF₂)₇(CH₂)₁₀OCOC(CH₃)═CH₂    -   CF₃(CF₂)₆CH₂OCOCH═CH₂    -   (CF₃)₂CF(CF₂)₁₀(CH₂)₂OCOCH═CH₂    -   (CF₃)₂CF(CF₂)₆(CH₂)OCOC(CH₃)═CH₂    -   (CF₃)₂CF(CF₂)₈(CH₂)₂OCOC(CH₃)═CH₂    -   CF₃CF₂(CF₂)₆(CH₂)₂OCOCH═CH₂    -   CF₃CF₂(CF₂)₈(CH₂)₂OCOCH═CH₂    -   CF₃CF₂(CF₂)₁₀(CH₂)₂OCOCH═CH₂    -   CF₃CF₂(CF₂)₆(CH₂)₂OCOC(CH₃)═CH₂    -   CF₃CF₂(CF₂)₁₀(CH₂)₂OCOC(CH₃)═CH₂    -   CF₃(CH₂)₇SO₂N(CH₃)(CH₂)₂OCOCH═CH₂    -   (CF₃)₂CF(CF₂)₆CH₂CH(OH)CH₂OCOCH═CH₂

The amount of the perfluoroalkyl group containing monomer used may rangefrom 40 to 95% by weight, preferably from 50 to 90% by weight, morepreferably from 60 to 85% by weight based on the copolymer.

Examples of another copolymerizable compound include ethylenicallyunsaturated monomers which are copolymerizable with monomers containingperfluoroalkyl or perfluoroalkenyl groups. Non-limiting examples of suchmonomers are (a) acrylic acid and methacrylic acid, and methyl, ethyl,propyl, 2-ethylhexyl, hexyl, decyl, lauryl, cetyl, stearyl, isobornyl,β-hydroxyethyl, glycidyl, phenyl, benzyl esters thereof (b) vinyl estersof fatty acid such as acetic acid, propionic acid, caprylic acid, lauricacid and stearic acid (c) styrene compounds (d) vinyl halides (e) vinylalkyl ketones (f) acryl amides and (g) dienes like isoprene.

Examples of quaternary ammonium compounds used in this invention includedialkyl(C₁₂-C₂₂)dimethyl ammonium chloride, alkyldimethyl benzaylammonium chloride, octadecyltrimethyl ammonium chloride,dialkyl(tallow)dimethylammonium chloride, dodecyltrimethylammoniumchloride, hexadecyltrimethyl ammonium chloride,biphenyltrimethylammonium chloride, alkylimidazoline quaternary salt,octadecyldimethylbenzylammonium chloride,polyoxyethylenedodecylmonomethylammonium chloride and1-hydroxyethyl-2-alkylimidazoline quaternary salt.

The amount of quaternary compound may be from 0.01 to 10 parts byweight, preferably from 2 to 7 parts by weight, based on 100 parts byweight of the polymer.

The aqueous medium in the present invention is preferably water or amixture of water and another water-miscible solvent. The water solubleorganic solvent having a flash point of at least 70° C. is employed asco-solvent. Examples include propylene glycol, dipropylene glycol anddipropylene glycol mono-methyl ether.

Example of a method for preparing the polymer include bulkpolymerization method, solution polymerization method, suspensionpolymerization method, emulsion polymerization method and the like; theemulsion polymerization method is preferable.

In the emulsion polymerization method, it is preferable to copolymerizethe monomers in the presence of quaternary ammonium compound/compoundsas surfactant in an aqueous medium having a polymerization initiator anda chain transfer agent.

A water soluble initiator is preferable and particularly a water solublesalt of an azo type compound is more preferable. Preferablepolymerization temperature is from 50 to 160° C. to assure formation ofa stable emulsion.

The chain transfer agent used in this invention includes mercaptans oralkyl mercaptans.

In the present invention, before starting emulsion polymerization, it ispreferable to have a mixture of monomers, quaternary ammonium salt andan aqueous medium subjected to mixing and dispersing. A solid content ofwater and oil-repellent composition of the present invention ispreferably from 10 to 40% w/w, more preferably from 20-30% w/w, keepingin view the emulsion stability and cost or the like.

Examples of the materials to be treated with water and oil-repellentcomposition of the present invention include textile fabrics such assingle fiber, complex fiber, cloth, leather, carpets or like, fur,paper, wood, plastics, glass, metals, bricks, ceramics, cement, whilethe preferable example includes textile fibers such as cotton, hemp,wool, silk and like, synthetic fibers such as polyamide, polyester, PVA,polyacrylonitrile, PP, PVC or like, semi synthetic fibers such asacetate, rayon or the like, inorganic fibers such as carbon fibers,glass fibers, asbestos fibers or like.

The water and oil-repellent composition of the present invention isdiluted to a concentration keeping its use in view. Any coating methodcan be employed depending on a kind of the material to be treated. Forexample, when employing a dip-coating method, a material to be treatedis dipped in a diluted solution of the water and oil-repellentcomposition, it is preferable to carry out a curing treatment at hightemperature (180° C.-200° C.).

For example, when treating textile fabrics such as nylon, polyester,cotton, etc., a non volatile content concentration is preferably from0.1 to 3% w/w, more preferably from 0.5 to 2% w/w in order to achieveexcellent water and oil repellency while maintaining satisfactory handfeel softness of the textile and keeping the economical advantages inview. It is preferable to carry out a heat treatment and curing at 180to 200° C. for 100 to 300 seconds.

The water and oil-repellent composition of the present invention impartswater and oil repellency excellent in terms of durability withoutaffecting the physical appearance of the textile. The processing methodis convenient and provides economical affordability.

Preferred Embodiments of the Present Invention

The following examples which do not limit the present invention, furtherillustrate the present invention in detail.

The properties are measured as follows:

Water Repellency

Aqueous solution of isopropyl alcohol (IPA) shown in Table 1 ispositioned on a test fabric, the water repellency is evaluated accordingto AATCC-TIM 118-1992 and then expressed as water repellency grade shownin Table 1.

TABLE 1 Water Repellency Test Liquid Grade (Volume Ratio %) 10  IPA 1009 IPA 90/WATER 10 8 IPA 80/WATER 20 7 IPA 70/WATER 30 6 IPA 60/WATER 405 IPA 50/WATER 50 4 IPA 40/WATER 60 3 IPA 30/WATER 70 2 IPA 20/WATER 801 IPA 10/WATER 90 W WATER 100 0 Inferior to w

Oil Repellency

According to AATCC-TM118-1992, several droplets (diameter: 4 mm) of thetest liquid shown in Table 2 are positioned on two sites of test fabricand penetration states of the test liquid are determined after 30seconds. The oil-repellency is expressed by the oil-repellency gradeshown in Table 2

TABLE 2 Oil Surface Tension Repellency (Dyne/cm, Grade Test Solution 25°C.) 8 n-Heptane 20.0 7 n-octane 21.8 6 n-decane 23.5 5 n-dodecane 25.0 4n-tetradecane 26.7 3 n-hexadecane 27.3 2 n-hexadecane:Nujol (35:65) 29.61 Nujol 31.2 0 Inferior to 1 —

Preparation of Repellent Composition

EXAMPLE 1

-   1. Perfluoroalkylethyl acrylate C_(n)F_(2n+1)CH₂CH₂OCOCH═CH₂,    mixture of n=6-16, average value of n=9, 150 g-   2. Stearyl acrylate, 53.5 g-   3. Hydroxyethylacrylate, 10 g-   4. Stearyltrimethyl ammonium chloride, 5 g-   5. Dodecyl mercaptan, 0.5 g-   6. Deionized water, 200 g-   7. Dipropylene glycol, 98 g-   8. Azobisisobutylamidine dihydrochloride, 0.85 g

Components 1-7 were charged into a 1 L autoclave and emulsified at 75°C. for 20 minutes by sonification. Under nitrogen cover, component 8 wasadded and the reaction was continued for 8 hours to give an aqueouswater and oil-repellent dispersion.

EXAMPLE 2-4

Procedure of Example 1 was repeated with different emulsifyingquaternary ammonium compounds:

Example Surfactant 2 Dioctadecyldimethylammonium chloride 3Benzyldodecyldimethylammonium chloride 4 Lauryltrimethylammoniumchloride

Preparation of Treating Solution

A treating solution for processing was prepared by adjusting a water andoil-repellent composition (Examples 1-4) with water in such a manner asto make a non-volatile content concentration 1% w/w.

Preparation of Cloth for Evaluating Water and Oil-Repellency

An undyed mercerized cotton (100%) broadcloth was dipped in a treatingsolution, and the wet cloth thus dipped was subjected to squeezingbetween two rubber rollers in such a manner as to make a wet pickup 70%w/w/. The cloth thus treated was dried at 110° C. for 200 seconds andwas then heat-treated at 180° C. for 180 seconds to prepare a testcloth.

TABLE 3 Water and Oil Repellency Initial Durability HL 0 HL 3 Water OilWater Oil Example Repellency Repellency Repellency Repellency 1 10 6 8 42 10 7 8 4 3 10 7 8 4 4 10 6 8 4 Note: HL-0: initial (Before washing andcleaning) HL-3: After 3 hand washes

Effects of Invention

According to the present invention, the aqueous water and oil-repellentcomposition is disclosed having durable water and oil repellency andexcellent storage stability.

1. An aqueous water and oil repellent composition which comprises: a. Anacrylate or methacrylate copolymer containing perfluoroalkyl orperfluoroalkenyl group. b. A surfactant comprising a quaternary ammoniumcompound c. An aqueous medium containing an organic co-solvent
 2. Thecomposition of claim 1 wherein said copolymer compound comprises arepeat unit derived from a fluoroalkyl group-containing monomer, afluoroalkyl group containing maleate or fumarate.
 3. A method ofmanufacturing said copolymer of claim 1 wherein a perfluoroalky orperfluoroalkenyl group monomer is polymerized with ethylenicallyunsaturated monomers, mixed with a chain transfer agent, said surfactantof claim 1 and emulsified in the medium of an organic cosolvent.
 4. Themethod of claim 2 wherein said perfluoroalkyl or perfluoroalkenyl groupcontaining acrylate or methacrylate groups is selected from the group ofcompounds comprising: a. CF₃(CF₂)₇(CH₂)₁₀OCOCH═CH₂, b.CF₃(CF₂)₇(CH₂)₁₀OCOC(CH₃)═CH₂, c. CF₃(CF₂)₆CH₂OCOCH═CH₂, d.(CF₃)₂CF(CF₂)₁₀(CH₂)₂OCOCH═CH₂, e. (CF₃)₂CF(CF₂)₆(CH₂)OCOC(CH₃)═CH₂, f.(CF₃)₂CF(CF₂)₈(CH₂)₂OCOC(CH₃)═CH₂, g. CF₃CF₂(CF₂)₆(CH₂)₂OCOCH═CH₂, h.CF₃CF₂(CF₂)₈(CH₂)₂OCOCH═CH₂, i. CF₃CF₂(CF₂)₁₀(CH₂)₂OCOCH═CH₂, j.CF₃CF₂(CF₂)₆(CH₂)₂OCOC(CH₃)═CH₂, k. CF₃CF₂(CF₂)₁₀(CH₂)₂OCOC(CH₃)═CH₂, l.CF₃(CH₂)₇SO₂N(CH₃)(CH₂)₂OCOCH═CH₂, and m.(CF₃)₂CF(CF₂)₆CH₂CH(OH)CH₂OCOCH═CH₂
 5. The method of claim 2 wherein theconcentration of said perfluoroalkyl or perfluoroalkenyl group is 40 to95% by weight.
 6. The method of claim 2 wherein polymerization iscarried out within the temperature range of 50 to 160° C.
 7. The methodof claim 2 wherein said ethylenically unsaturated monomer is selectedfrom a group comprising (a) acrylic acid and methacrylic acid, andmethyl, ethyl, propyl, 2-ethylhexyl, hexyl, decyl, lauryl, cetyl,stearyl, isobornyl, β-hydroxyethyl, glycidyl, phenyl, benzyl estersthereof (b) vinyl esters of fatty acid, propionic acid, caprylic acid,lauric acid and stearic acid (c) styrene compounds (d) vinyl halides (e)vinyl alkyl ketones (f) acryl amides and (g) dienes.
 8. The method ofclaim 1 wherein said chain transfer agent is selected from a groupcomprising mercaptans or alkyl mercaptans.
 9. The method of claim 2wherein said organic solvent is selected from a group comprisingpropylene glycol, dipropylene glycol and dipropylene glycol mono-methylether.
 10. The composition of claim 1 wherein said quaternary ammoniumcompound is selected from a group comprising of dialkyl(C₁₂-C₂₂)dimethylammonium chloride, alkyldimethyl benzayl ammonium chloride,octadecyltrimethyl ammonium chloride, dialkyl(tallow)dimethylammoniumchloride, dodecyltrimethylammonium chloride, hexadecyltrimethyl ammoniumchloride, biphenyltrimethylammonium chloride, alkylimidazolinequaternary salt, octadecyldimethylbenzylammonium chloride,polyoxyethylenedodecylmonomethylammonium chloride and1-hydroxyethyl-2-alkylimidazoline quaternary salt.
 11. The compositionof claim 1 wherein the concentration of said of quaternary compound isfrom 0.01 to 10 parts by weight of the polymer.
 12. A method ofprocessing a textile, comprising treating the textile with saidrepellent composition according to claim 1, comprising steps of: (1)preparing a treatment composition by diluting said repellent, (2)applying the treatment composition to a textile, and (3) washing thetextile with water and (4) dehydrating the textile.
 13. The method ofclaim 10 wherein said treatment composition is dilute to 0.1 to 3% usingwater.